Escrow has closed, the capital fundraising machine is humming along and now the 18,000-square-foot structure on Highway 12, across from Maxwell Village shopping center, is being fleshed out for the new Sonoma Valley Health Center.

The building at 19270 Sonoma Highway, which was formerly a commercial strip mall, may look like a complete building from the outside. But it's really nothing more than a structural shell that by July will house a state-of-the-art primary-care facility that will include a dental clinic.

The first order of business for construction workers is to trench the slab of concrete that the building sits on for water and sewer pipes, as well as installing ductwork for heating, ventilation and air conditioning.

"The work is pretty substantial. It's literally a shell," said Cheryl Johnson, the health center's CEO.

There are no interior walls or insulation, let alone all the wiring, plumbing, gas lines, communications network systems or lighting that the facility requires, she said.

The new health center, eight years in the planning, comes at a critical time when the federal Affordable Care Act is adding millions of Americans to the ranks of the insured. Johnson said the health center expects the number of patients to increase from 7,000 to 9,100 in the near future, an increase of 30 percent.

Construction should be completed by June, though the clinic won't open until July.

"We have to move in all the furniture, calibrate equipment, do run-throughs," Johnson said.

Currently, the health center's medical and support staff and administration workers are housed in three separate locations. All current services and new ones, such as the dental clinic, will be brought together in the new clinic, which will have 20 exam rooms plus classrooms and other facilities to provide social services to patients.

The 18,000-square-foot building will double the size of the health center's operations.

"Overall, for us it's really amazing," Johnson said. "Right now, we can't wait for the day when it opens."

The new building will not only allow the health center to add new services, it will permit the integration of all services.

"More of a one-stop shop is really something we're looking forward to," Johnson said.

The price tag for construction, architect and engineering fees, permit work, site work and other items is about $5.4 million. The land financing was about $6.2 million.

You can reach Staff Writer Martin Espinoza at 521-5213 or martin.espinoza